Are the command levels below LEVEL_HERO? The wizhelp command looks for skills that are equal to LEVEL_HERO, 100 in stock, or higher. If you increased MAX_LEVEL then LEVEL_HERO, MAX_LEVEL - 5, just might be higher then the highest level commands now which means that they won't show under wizhelp.

Actually, isn't it the case if he raised the levels above 100 the if check would no longer show up in wizhelp?

I think you need to go through and reset the imm commands to their new levels before they'll show up. Or you can change this line (found in act_wiz.c - function do_wizhelp)

if( cmd->level >= LEVEL_HERO && cmd->level <= get_trust( ch ) )

To

if( cmd->level >= 101 && cmd->level <= get_trust( ch ) )

That should do it. But the thing to remember is this is only so you can see the commands. You'll want to change the levels or the players could potentially access these commands. Also, if you just want to raise a players level cap, that is something that is possible. SWR is actually set so you can have a player level to 110 but their top_level remains at 100. Meaning their classes go up in levels, but not there overall level.

I'd check an imm only command real quick, like goto, and confirm the level using cedit. It's probably still a level 101, I think, command. You'll need to change it to 1501 for it to show up under wizhelp. And do the same for all the other imm only commands as well if you want them showing properly.

If you know you're going to probably go back to a lower level cap I'd suggest making a backup of the commands.dat file in the system dir, then changing level commands. Once you've done all your testing you can put the old copy back and not have too much trouble resetting, if needed, the commands again.

Edit @Keirath:
Yeah, I looked at what I originally wrote and went, "Hey, that's not what I meant to say!"

In the system folder, commands.dat holds the commands. You can search for something like goto and it will show its assigned level. Be careful though, if you mess up the file commands may not load correctly.